I suspect most great writers are also terrible writers. It all depends what you show people. I think this is the key to beating the empty screen. Because it's the pressure that kills, right? The urge to write the next great novel, or make a boatload of money with scandalous, (un)literary smut, or prove what a deep, deep thinker you are. The pressure is too consistent to ever get anything done. So, yield to mediocrity, accept that the next word you write is likely going to be the wrong word and keep going anyway. The real worst case scenario isn't that you might write something bad. The worst case scenario is that you might write nothing at all.